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NAEP Analysis and Scaling → Estimation of NAEP Score Scales → NAEP Assessment IRT Parameters → Mathematics Assessment IRT Parameters → IRT Parameters for Items in the Algebra Subscale, Grade 4 Mathematics Combined National and State Assessment, by Item and Block: 2015

NAEP Technical DocumentationIRT Parameters for Items in the Algebra Subscale, Grade 4 Mathematics Combined National and State Assessment, by Item and Block: 2015

IRT parameters for items in the algebra subscale, grade 4 mathematics combined national and state assessment, by item and block: 2015
BlockItemNAEP ID aj bj cj dj1 dj2 dj3 dj4
M3
7M3425010.82-0.480.15††††
10M3448011.55-0.160.26††††
M4
2M1468010.48-0.74†††††
M5
8M2189010.63-2.34†††††
12M2193010.540.380.22††††
M6
7M3421010.510.11†-0.180.18††
14M3452011.561.010.16††††
M7
7M3468CL0.64-0.35†1.43-1.43††
10M3485010.830.050.15††††
13M3475011.16-0.220.18††††
M8
5M2406010.57-1.65†††††
13M2311CL0.790.42†0.090.43-0.52†
M9
4M2276010.67-0.970.08††††
12M2268011.010.16†††††
M10
1M2197010.98-1.870.08††††
4M2200010.46-1.82†-1.811.81††
M11
5M1566010.700.190.09††††
9M1562010.270.010.15††††
16M1610CL0.201.09†-0.95-1.84-0.683.47
M12
5M2292010.86-0.700.12††††
8M2288011.461.180.42††††
† Not applicable; c parameters are not estimated for the two-parameter logistic model or generalized partial credit models, and d parameters are not estimated for two-parameter or three-parameter logistic models.
NOTE: For item j, aj represents the discriminatory power of the item, bj represents a location parameter related to item difficulty, cj represents the guessing parameter, and dji represents the category threshold parameter for category i. The c parameter value is assumed to be exactly zero and is not estimated for items scaled with the two-parameter logistic model. For item j, dji may not sum to zero because of rounding.
SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2015 Mathematics Assessment.

Last updated 17 November 2021 (ML)